Ah - I misread your comment earlier, and I also didn't see that the other ISOs were hosted by Microsoft. In fact I misread most of this project because I was pre-emptively suspicious :) I guess the real problem is these older installations are in a bit of a grey area so I can see the value Bob Pony is actually providing here.
I'm pretty sure these ISOs are NOT modified though I am a bit skeptical of some of these sources. Editing my first comment to clarify that I misread this...
Unless what you're saying is that this is a modified ISO to remove activation.
if thats the case then, I agree wholeheartedly. Just explaining why you dont/cant use the standard microsoft.com links.